This looks good. But I do have some doubts regarding its querying abilities. As far as I can tell, you can only define a range of data to be fetched (limit). If I want to query for a particular value, i.e. fetch all users matching name - that doesn't seem possible. Or am I missing something?

It's possible, but you'll have to structure your data slightly differently. There's a blog post detailing one possible approach: https://www.firebase.com/blog/2013-04-12-denormalizing-is-no...

We're working hard in regards to adding more powerful query support to Firebase though and would love your feedback so we can improve the API (just email support@firebase.com).

Interesting. Have you thought about using JSON to describe views (like in QML)?

It's already something I'm considering for a future release.

Having said that, I'm not sure that the readability of JSON (when producing an interface like in QML) is as straightforward as XML.

Well I personally find JSON easier to read and write than XML. Though it might be different for some people, I don't know. It would differentiate the whole thing a bit more from the usual XML approach by interface builder.

Will definitely take that onboard